The proposed research is to determine the effect of electrical stimulation on the tissue growth into porous dental root with a solid core. In addition, the healing characteristics of the gingival cervix affected by the electrical stimulation will be studied. To simplify the experiment two types of implants (subgingival and transgingival) will be made from polymethylmethacrylate. The subgingival (1.05 cm long X 0.45 cm dia.) and transgingival implants will be identical except that the latter will have a solid neck portion (0.38 cm long X 0.25 cm dia) protruding through the mucosa. The electrode (Pt-13%Rh) will be wound around the solid root core (0.8 cm long X 0.25 cm dia.) before porous portion is made. The implants with negative electrode will be placed in the distal root socket of the 4th premolar of dogs. The other electrode will be buried in the alveolar bone distal to the third premolar. The stimulation will be done at one current level (approximately 4 micron A) by using an 1.4V mercury battery with a resistor in series encapsulated by silicone elastomer. In addition to the conventional clinical evaluation of the implant the actual strength of the implant/tissue interface will be determined by using a pull-out test on an Istron machine. The quantification of the amount of tissue grown in the pores by chemical assaying and microscopic examination will be correlated to the strength of the interface for both stimulated and non-stimulated control specimens.